Nov 1 (Reuters) - British lawmaker Peter Hain said on Wednesday he has asked finance minister Philip Hammond to refer an unidentified UK bank to regulators for an investigation into possible involvement in alleged money laundering involving South Africa’s Gupta family.

Hain had hand delivered documents to Hammond on Tuesday that he said showed participation of an unidentified British bank in illegal transfers of funds from South Africa made by the Gupta family over the last few years.

The Guptas, a family of Indian-born businessmen in South Africa, are under scrutiny for their close ties to South African President Jacob Zuma and have been accused of unduly influencing the awarding of state tenders. The family has denied any wrongdoing and no charges have been filed.

“(I) named the British bank concerned and asked that he (Hammond) again refer these to the Serious Fraud Office, the National Crimes Agency, and the Financial Conduct Authority (FCA) for investigation”, Hain said in the House of Lords, according to a video on British parliament’s website.

The unidentified bank is HSBC Holdings Plc, the Financial Times reported, citing one person who has seen a letter Hain separately sent to the Treasury and the FCA. (on.ft.com/2gUNP6A)

HSBC and the FCA could not be reached for comment outside regular business hours.

This is not the first time the Labour politician has asked for a scrutiny of British lenders’ ties with the Guptas.

Hain had asked the finance ministry in October to look into the HSBC and Standard Chartered Plc’s possible ties to the Gupta family and Zuma and the FCA said it was in contact with those lenders.

The politician also wrote to Hammond in September requesting a probe of British banks’ involvement in money-laundering in South Africa. (Reporting by Ismail Shakil in Bengaluru; Editing by Lisa Shumaker)